Attack on the United States embassy in Baghdad

The Attack on the United States embassy in Baghdad occurred from 31 December 2019 to 1 January 2020 when the Iranian-backed Kata'ib Hezbollah, the Popular Mobilization Forces, and their sympathizers attacked the US embassy in the Green Zone of Baghdad, Iraq to protest the US airstrikes on Kata'ib Hezbollah in Iraq and Syria on 29 December. The embassy attack had no casualties, but Iran's dastard show of power in the region led to the US retaliating with another airstrike, killing the Iranian general Qasem Soleimani and PMF leader Abu Mahdi al-Muhandis.

Background
In the aftermath of the US withdrawal from Iraq in 2011, Iran began to assert its influence in the region, backing the Ba'athist government of Syria during the Syrian Civil War and arming the Iraqi Shia Popular Mobilization Forces militias during the Iraqi Civil War. Following the defeat of the Islamic State in Iraq in December 2017, the PMF leadership entered into politics as the "Fatah Alliance", forming a government alongside the powerful Saairoun party of the influential Shia cleric Muqtada al-Sadr. The new Iraqi government was staunchly pro-Iran, and anger at Iranian influence led to widespread protests in late 2019. On 27 December 2019, Iranian-backed militants fired 30 rockets at the K-1 Air Base in Kirkuk, killing an American civilian contractor and wounding 4 US and 2 Iraqi servicemen. This attack provoked a strong response from President Donald Trump, who retaliated by launching airstrikes against Kata'ib Hezbollah bases in both Syria and Iraq. These airstrikes killed 25 Shia militants, provoking outrage among militant Shi'ites in Iran and Iraq.

Attack
On 31 December 2019, following the funeral of the killed Kata'ib Hezbollah fighters, an angry mob of dozens of Iraqi Shi'ite militiamen from Kata'ib Hezbollah and the PMF marched into the Green Zone of Baghdad and surrounded the US embassy; Iraqi security forces permitted them to pass through a security checkpoint. The mob chanted "Death to America" and "Death to Israel" before scaling and throwing stones and water over the walls and using rams to attack the embassy's gates, windows, and doors. The protesters raised PMF flags and placed anti-American posters and sprayed anti-American graffiti on the walls, and militiamen set fire to the reception area of the embassy and stole paperwork. The few armed Americans stationed at the embassy fired tear gas and held off the hundreds of militiamen and protesters until one of their leaders announced via loudspeaker that the Americans had been sent a message; the protesters withdrew from the siege and then established tents outside of the embassy that evening, attempting a sit-in. Five hours later, 30 Iraqi troops in 7 armored vehicles arrived near the embassy walls, and 4 riot police vehicles were forced back by protesters. 100 US Marine Corps soldiers were deployed from Kuwait to reinforce the embassy. On 1 January, the protesters started a fire on the roof of the reception area, again forcing the Americans to fire tear gas. That same day, the PMU commanders ordered an end to the protests, having "rubbed America's nose in the dirt," as one protester bragged.

Aftermath
The attack, while bloodless, infuriated President Trump, who claimed that he was determined not to suffer a repeat of the 2012 Benghazi attack. On 2 January 2020, Secretary of Defense Mark Esper warned that the US would strike any Iraqi paramilitary group which it deemed a threat; in the morning hours of the next day, the US retaliated against Iran and the PMF by killing Quds Force general Qasem Soleimani and PMF commander Abu Mahdi al-Muhandis in an airstrike at the Baghdad International Airport.